ICDs deliver relatively high-energy cardioversion and/or defibrillation shocks to a patient's heart when a malignant tachyarrhythmia, e.g., atrial or ventricular fibrillation, is detected. ICDs typically operate in conjunction with one or more leads carrying a coil electrode(s) for delivering high-voltage shocking pulses. In addition to a coil electrode, the lead may carry pace/sense electrodes for sensing intracardiac electrogram signals (EGM) or subcutaneous ECG signals and for delivering low-voltage pacing pulses.
Numerous ICD systems are commercially available and may be used in conjunction with a variety of lead systems. Industry standards have been developed to prevent the insertion and electrical coupling of a high voltage lead terminal to a low voltage ICD connector module terminal and vice versa. Improper connection of electrical leads to the ICD may cause device damage, inappropriate or failed operation of the ICD, and undue risk to the patient.